Sharpening tool



c/T. RoTTLER SHARPENING TOOL April 9, 1935.

Filed May 2l, 1932 E INVENTOR B MMEY Patented Apr. 9, 1935 e l; j carence nazomer, seatuejwash., 1 .,Appucatanmy ai, 1932, `steal Nt. c12,7zs ""a-folaims.y (ol. sp1-'220) .Tg-My v,invention :relates ,the sharpening ef tool hits- Toolbits usedfin mahizietools Afrequently lose their keenshalipzedgetsandsincethey must be true and .sharp infractions :of thousandths of quent-1y, evenWheninade-fof very :hard material. L Y. It isv an object of any` f-invention,` then, .to proliv-ide .fafsimplertooli-,byvwhiclr tool bits may bezquickaccurately and conveniently sharpened. ilt .is I aiurther object to Ifproviders-uch a means Mwhich will eliminatev the probability :of ,any .of the :abra- .sivefof :which the :stone itself may.. be, 'formed or which mayfberappliedto :a finishing or Vlapping :surface of, the tool for fapplicationjto :the fbit, from coming intocontact with the )Contact surfaces :guiding-the sharpening `tool parts, :which surfaces `are placed atea definite angular .relationship to tire.-;edgegoftheitool. such contact of the abrasive would destroy-.the accuracy of the, sharpening tool. itself., and therefore vwould, make it sharpenftne tool incorrectly. or inaccurately.

It is a further object to provide such a tool which is simple and inexpensive in character, adapted to be used either while the tool bit is in place, held in a special holder or held in the hand, and one which is adjustable, if need be, to vary the angle of the point of the machine tool.

My invention comprises the novel tool and the novel method of sharpening a tool bit, as shown in the accompanying drawing, described in this specication, and as will be more particularly defined by the claims which terminate the same. In the accompanying drawing I have shown my tool, and have illustrated the method ofV sharpening tool bits.

Figure 1 is a plan View `of the tool, parts being shown in operative position.

Figure 2 is a part section and part elevation, likewise showing partsin operative position.

Figure 3 is a perspective View of the two parts of the tool.

Machine tool bits may take various forms, but for purposes of illustration I-l have shown a straight bar 9 having one end beveled away to form a point or edge 90. Y' This is the working point of the tool, and must be accurately sharpened so that its cutting edge or edges bear a denite relationship to the length of the bit, which in use is held rigidly in a holder, or to the axis or 50 angle of the work against which the bit bears.

Unless this very definite relationship of the cutting edge of the bit is maintained, the micrometer adjustments of the tool holder become inaccurate, the positioning of the tool becomes a matter of 55 guess Work, and 'exactV reproduction of. a part is @projected "thrtmghr4 a.

impossible. 'Moreoven unlessthevarious angles A arehcorrect, theibit will not do its work-properly,

and sa rough finish or :uneven sur-face lis the result.

.In effect, my `invention comprises, three -elements-,faplate ,-I a ,-memberlassociated with the plate land adapted .to engage thebit, and to hold j it in'vwdeliite-lelationship tothe working surface .ID fof the, @1 -abe, and iainember, generally designated by the numeral 3, having an abrasirfe-kbearing surface-30 orbeing in yitself abrasive in charactor. Y When; the Ledge -to-be `suppliedrto `the tool bit is Atogbze straight, the plate I may conveniently jtalge the for-m :ofi-a fdisk, circular ,or of any lother convenient shape, the surface III of ywhich is E175 fplane. Preferably *ftheydisk isapertured in its I gcentral portion, as indicated Aat I .I aperture --is of 4Va size to permit gany fordinary :tool fbitwto be :Thefunction '.ofv themember 2 is toV 'engage'the .i210

.tool lbit,and itoxsupport the disk I so that fa bitf held in or engaged by the member 2 is held in definite relationship to theplane ofthe surface IU. Thus the member 2V may be formed as an angular member havingone or two flanges` 20 and 2| against one or both of which the sides' of the bit 9 may be fitted as a gauge.

The manner of support of the plate or disk IV from the member 2 is immaterial. If a certain angle is desirable for a large'amount of sharpening, the connection may be a rigid one at thedesired angle. If the toolis designed for sharpening-at diiferent angles, the connection may be adjustable, and preferably it is adjustable in two direc# tions along axes both of which are at right angles to each other and to the length of the bit. Thus, as is best seen in Figure 2, a strap `4 is pivotally connected by the boltc40 and Wing nut 4I to the under side ofthe member 2, and a second strap 5, secured to the disk |is pivotally connectedrby the nut and clamping screw 5| to the strapl. Adjustment may be accomplished in the manner indicated bythe dash lines in Figures 1 and 2. y 1

'I'he member 3 has lcertain elements, spaced from each other, which jointly dene a plane surface which is complemental to the surface Ill of the disk I, and which, Whenin engagement vwith the surface IIJ, hold the abrasive-bearing surface 30 away from the surfacel. The abrasive-bearing surface must not come in direct contact with the plate, and preferably it does not come in direct contact with those elements which bear upon the plate. The object of this, of course, is to prevent abrasive getting between the re1- atively movable parts, andthus, by Wearing away the bearing elements or the plate, to destroy the formed upon a bar 32, of cast iron, for instance,

the surface ofwhich is parallelto the plane defined by the'edges 3 I The sides of the bar 32 are spaced from the anges of the channel-shaped member 3, as is best seen in Figure 1.

As has already been'mentioned, the bar ,3

may itself be of abrasive material. Itmay be'of stone, for instance, but if it isintended'to re-` ceive one of the harder abrasives-boron carbide, A

for instance, which is employed for sharpening tool bits of hard material, such as tungsten carbide, for instanceit will usually be of cast iron.

` When such an abrasive is employed it may be applied to the-surface 30 in any suitable manner, for

-'instance, byapplying olive oil to the surface 3D andthen spreading the abrasive Apowder-thereon. Y

Care is taken tokeepthe oil andthe abrasive, the latter atleast, from the-edges 3| and, of

course, from the surface l0. The. spacing of the bar 32-fromthe fianges of the channel 3 facilitates this.

The disk having been-now adjusted to the proper angle with relation to the length of the bitv 9, and the bit having been'properly applied to the member 2 and projectedfslightly through the aperture in the disk, the member 3 is engaged with the surface'l and its surface 30 with'the point of the tool.- The member 3 is vnow moved relativelyr to the bit in a mannerfcommon in grinding-or lapping devices, and gauged bythe contact between the surfaces 3l and l0, thepoint of the bit is quickly, convenientlyfand very accurately sharpened. Its angle` of course, will depend upon the angle at which the disk has been set with respect to the channel 2.

It is evident that it is immaterial whether the bit 9 be held in some manner and the sharpening tool applied thereto, or Whether the bit be removed from any holder and be applied within the sharpening tool and held by hand.

What I claim as my invention is:

1. A tool for sharpening machine tool bits comprising an aperturedcontact .plate, means associated therewith for engaging the ,bitfso that the point of the latter projects through the aperture, and to Vmaintain the bit in definite angular relationship. to that surface of the plate past which the edge of the bit projects, a complemental Y means having elements adapted to bear upon and move over such surface of the plate, and'having an abrasive-bearing surface recessed Within the plate-engaging elements to engage the projecting edge of the bit, and to be held from contact with the plates surface, and means to x the ibitengaging-means inany Ydesired angular relationship relativeto the plates surface.

A 2. A tool for sharpening machine tool bits comprising an aperturedcontact plate, means associated therewith for engaging the bit so that the point of the latter projects through the aperture, and to hold the bit in deiiniterelationship to that surface of the'plate past which the edge of the bit'projects; a'complemental means having elements adapted ,to bear upon and move over such surface of the plate, 'and having an abrasivebearing surface' recessed Within the plate-engaging elements to engage the projecting edge ofthe 

